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问题描述
我正在尝试遵循以下示例，但是当我尝试对其进行编译时，出现此错误:
I'm trying to follow this example but when I try to compile it, I have this error:
Error: Unable to initialize main class com.amazonaws.services.kinesisanalytics.aws
Caused by: java.lang.NoClassDefFoundError: org/apache/flink/streaming/api/functions/source/SourceFunction
该错误是由于以下代码引起的:
The error is due this code:
private static DataStream<String> createSourceFromStaticConfig(StreamExecutionEnvironment env) {
Properties inputProperties = new Properties();
inputProperties.setProperty(ConsumerConfigConstants.AWS_REGION, region);
inputProperties.setProperty(ConsumerConfigConstants.STREAM_INITIAL_POSITION, "LATEST");
return env.addSource(new FlinkKinesisConsumer<>(inputStreamName, new SimpleStringSchema(), inputProperties));
}
我想这是有问题的行:
return env.addSource(new FlinkKinesisConsumer<>(inputStreamName, new SimpleStringSchema(), inputProperties));
这是我的Maven依赖项:
This are my maven dependencies:
可能是什么问题?任何依赖关系，版本?
What could be wrong? any dependencies, version?
注意:如果我注释有问题的行，则程序可以正常运行.
Note: If I comment the problematic line, the program run without problem.
POM文件
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>as</groupId>
<artifactId>a</artifactId>
<version>1</version>
<packaging>jar</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<geotools.version>21-SNAPSHOT</geotools.version>
<java.version>1.8</java.version>
<scala.binary.version>2.11</scala.binary.version>
<flink.version>1.6.2</flink.version>
<kda.version>1.0.1</kda.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.0.0</version>
<executions>
<!-- Run shade goal on package phase -->
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<artifactSet>
<excludes>
<exclude>org.apache.flink:force-shading</exclude>
<exclude>com.google.code.findbugs:jsr305</exclude>
<exclude>org.slf4j:*</exclude>
<exclude>log4j:*</exclude>
</excludes>
</artifactSet>
<filters>
<filter>
<!-- Do not copy the signatures in the META-INF folder.
Otherwise, this might cause SecurityExceptions when using the JAR. -->
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>com.amazonaws.services.kinesisanalytics.aws</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>org.locationtech.jts</groupId>
<artifactId>jts-core</artifactId>
<version>1.16.0</version>
</dependency>
<dependency>
<groupId>org.geotools</groupId>
<artifactId>gt-geojson</artifactId>
<version>${geotools.version}</version>
</dependency>
<dependency>
<groupId>org.geotools</groupId>
<artifactId>gt-geojsondatastore</artifactId>
<version>${geotools.version}</version>
</dependency>
<dependency>
<groupId>org.geotools</groupId>
<artifactId>gt-main</artifactId>
<version>${geotools.version}</version>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-kinesisanalytics-runtime</artifactId>
<version>${kda.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-kinesis_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-kinesisanalytics-flink</artifactId>
<version>${kda.version}</version>
</dependency>
</dependencies>
</project>
推荐答案
您的错误在这里:
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
<scope>provided</scope>
</dependency>
范围是provided.这意味着，您的程序希望该库在运行时可访问，但找不到它.
The scope is provided. This means, that your program expects that library to be accessible during runtime, but it can't find it nowhere.
NoClassDefFound表示可在编译时访问它，但在执行期间无法访问.
NoClassDefFound means it was accessible for compile time, but not during the execution.
将范围更改为compile ，以解决此问题.另外，您可以此处有关更多技术信息.
Change the scope to compile in order to resolve this issue. Also, you can take a look here for more technical info.
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